resin family

Filled Polymers

Additives, fillers and reinforcements.

All Resin Families

Additives, fillers, and reinforcements are used to change and improve the physical and mechanical properties of plastics. In general, reinforcing fibers increase the mechanical properties of polymer composites while particular fillers of various types enhance a particular property.

Additives and Reinforcements

Listed below you will find many of the common additives and reinforcements used in polymers and their effect on properties:

  • Glass fiber: Increase strength and stiffness
  • Carbon fiber: Increase stiffness and electrical conductivity
  • Minerals: Reduce warpage
  • Impact modifiers: Increase toughness and impact properties
  • Anti-oxidants: Reduce oxidation and yellowing
  • UV stabilizers: Improve weatherability and UV resistance
  • Lubricants: Improve flow and mold release
  • Colorants: Custom coloring 
  • Nucleating agents: Reduce cycle times during molding
  • Flame retardants: Improve flammability ratings
  • Tribological (PTFE, Silicon, Moly): Improve friction and wear properties
  • Conductive additives: Improve electrical conductivity


These are but a few of the more common fillers and reinforcements. Need something even more specialized? Amco Polymers can design a material around your needs.